Substrate for liquid crystal display and liquid crystal display utilizing the same

Abstract

The generation of residues or flakes of a color filter is suppressed to eliminate conduction failures on an LCD substrate having a color filter on an array substrate. A passivation film formed between a pixel electrode formed in each of a plurality of pixel regions and a TFT for driving the pixel electrode has a multi-layer structure constituted by SiN layers and a SiO layers, and the SiO layer is located at the top of the film. A resin CF layer is formed on the passivation film having such a multi-layer structure. Since the resin CF layer is formed directly on the SiO layer, reduction of the adhesion of the same is suppressed. As a result, the color filter is unlikely to come off when the resin CF layer is formed, and residues of the color filter is unlikely to be generated when a contact hole is formed in the resin CF layer. This suppresses conduction failures and makes it possible to provide a reliable TFT substrate and LCD having high display characteristics.

1. A substrate for a liquid crystal display, comprising:
 a switching element formed in a pixel region; 
 a resin color filter layer formed in the pixel region; 
 a pixel electrode formed on the resin color filter layer; and 
 a contact hole formed through the resin color filter layer to electrically connect the switching element and the pixel electrode, and the contour of the bottom of the contact hole having different length in longitudinal and transverse directions thereof and having round corners. 
 
     
     
       2. A substrate for a liquid crystal display according to  claim 1 , wherein the ratio between a major axis and a minor axis of the contour of the bottom (ratio between major and minor axial lengths=minor axial length/major axial length) is 0.5 or less. 
     
     
       3. A substrate for a liquid crystal display according to  claim 1 , wherein the area inside the contour of the bottom is 600 mm2 or less. 
     
     
       4. A substrate for a liquid crystal display according to  claim 1 , wherein an opening area inside the contour of the bottom varies depending on the position where the resin color filter layer is provided. 
     
     
       5. A substrate for a liquid crystal display according to  claim 1 , wherein the opening area inside the contour of the bottom is different for each color of the resin color filter layer. 
     
     
       6. A substrate for a liquid crystal display according to  claim 1 , wherein the resin color filter layer is formed from a negative type photosensitive material. 
     
     
       7. A liquid crystal display comprising:
 a base substrate having a pixel electrode formed in each pixel region, a switching element for driving the pixel electrode, and a color filter layer formed between the switching element and the pixel electrode; 
 an opposite substrate provided opposite to the base substrate; and 
 a liquid crystal layer sandwiched between the base substrate and the opposite substrate, wherein a substrate for a liquid crystal display according to  claim 1  is used as the base substrate.